[Beignet] [PATCH] GBE: Fix a bitcast from float vector to wide interger issue in legalize pass.

[Ruiling Song]

When bitcast from <4 x float> to i128, we should not use extractelement directly.
Instead, we cast <4 x float> to <4 x i32>, then use extractelement to get
individual element.

Signed-off-by: Ruiling Song <ruiling.song at intel.com>
---
 backend/src/llvm/llvm_legalize.cpp |    9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/backend/src/llvm/llvm_legalize.cpp b/backend/src/llvm/llvm_legalize.cpp
index ea0e75a..bb09eab 100644
--- a/backend/src/llvm/llvm_legalize.cpp
+++ b/backend/src/llvm/llvm_legalize.cpp
@@ -516,8 +516,15 @@ namespace gbe {
       Type *splitTy = vecTy->getElementType();
       unsigned elements = srcTy->getPrimitiveSizeInBits()/splitTy->getPrimitiveSizeInBits();
       // bitcast large integer from vector, so we do extractElement to get split integer
+      unsigned splitSz = splitTy->getPrimitiveSizeInBits();
+      Value *src = p->getOperand(0);
+      // if it is cast from <4 x float> to i128
+      // we cast <4 x float> to <4 x i32> first
+      if (!splitTy->isIntegerTy())
+        src = Builder.CreateBitCast(src, VectorType::get(IntegerType::get(p->getContext(), splitSz), elements));
+
       for (unsigned i = 0; i < elements; i++) {
-        Value *NV = Builder.CreateExtractElement(p->getOperand(0),
+        Value *NV = Builder.CreateExtractElement(src,
                       ConstantInt::get(IntegerType::get(p->getContext(), 32), i));
         split.push_back(NV);
       }
-- 
1.7.10.4